As an example, a conventional data processor receives and decodes data broadcast at intervals, and stores data decoded from the data broadcast in a memory device. The conventional data processor does not receive and decodes the data broadcast in an inactive period. Therefore, the conventional data processor can reduce its electric power consumption by stopping supplying an electric power in the inactive period (see for example patent document 1).    Patent document 1: Japanese Patent Laid-Open Publication No. H11-122586